This disclosure relates generally to a vehicle-to-vehicle communication methods, and more particularly to a protocol for achieving enhanced communication reliability on wireless communication links.
Maintaining real-time communications among mobile devices is critical for applications such as vehicle safety (e.g., vehicle collision avoidance), subscription-based mobile user services (e.g., user notification), and distributed coordination (e.g., autonomous air/ground/underwater vehicle formation). To enable widespread deployment of distributed mobile devices such as networked vehicles, one of the major challenges to address is to scale the communication to 10s or 100s of mobile nodes in close proximity while maintaining low message latency. Current approaches broadcast messages from one node to all the other nodes within the communication range without flow control, thus wiping out an entire channel that could be used by other devices.
Emerging technologies and standards such as distributed sensor networks, IEEE Pervasive Computing Magazine special issue, No. 1, January–March 2002, and DSRC (Dedicated Short Range Communication) for vehicle-to-vehicle communication, or the more established technology of 802.11/Bluetooth can enable a wide range of applications such as road safety (e.g., collision avoidance, merge assistance), environmental monitoring (vehicle/people tracking), mobility (mobile information subscription and delivery), device monitoring and service (vehicle/machine health monitoring and diagnostics). For example, the automotive industry alliance on safety (VSCC—Vehicle Safety Communication Consortium), with participation from almost all the major US and foreign auto makers, is basing their next-generation vehicle road safety applications on the DSRC platform.
However, scalability is one of the main issues in deploying the technology for time critical applications such as road safety. As the number of devices (e.g., vehicles) in a neighborhood increases, and the devices are moving (as in vehicles) and spatial proximity relations are constantly changing, managing communication among the mobile devices to guarantee timely delivery of critical messages, such as an imminent collision, becomes the paramount concern. Since bandwidth in technologies such as DSRC or 802.11 is still limited, the desired goal is to minimize unnecessary bandwidth consumption such as blindly repetitive broadcasting to everyone within the listening range, as is often the case with current technology.
A key objective of V2V communication is to reliably provide warnings about hazardous situations to drivers in time for them to react, it is necessary to have a reliable transport protocol specifically designed for V2V communication to satisfy the stringent requirements for reliability and timeliness in safety-critical scenarios.